Updated Connection Pool

- Merge nodes with same url but different id during update
- Cache auth data if provided when adding a connection

lib/ConnectionPool.js

@@ -11,6 +11,7 @@ class ConnectionPool {
     this.connections = new Map()
     this.dead = []
     this.selector = opts.selector
+    this._auth = null
     this._ssl = opts.ssl
     this._agent = opts.agent
     // the resurrect timeout is 60s
@@ -200,10 +201,26 @@ class ConnectionPool {
     if (typeof opts === 'string') {
       opts = this.urlToHost(opts)
     }
+    // if a given node has auth data we store it in the connection pool,
+    // so if we add new nodes without auth data (after a sniff for example)
+    // we can add it to them once the connection instance has been created
+    if (opts.url.username !== '' && opts.url.password !== '') {
+      this._auth = {
+        username: opts.url.username,
+        password: opts.url.password
+      }
+    }
     if (opts.ssl == null) opts.ssl = this._ssl
     if (opts.agent == null) opts.agent = this._agent
 
     const connection = new this.Connection(opts)
+    if (connection.url.username === '' &&
+        connection.url.password === '' &&
+        this._auth != null) {
+      connection.url.username = this._auth.username
+      connection.url.password = this._auth.password
+    }
+
     debug('Adding a new connection', connection)
     if (this.connections.has(connection.id)) {
       throw new Error(`Connection with id '${connection.id}' is already present`)
@@ -267,6 +284,18 @@ class ConnectionPool {
         if (oldConnection.status === Connection.statuses.DEAD) {
           this.markAlive(oldConnection)
         }
+      // in case the user has passed a single url (or an array of urls),
+      // the connection id will be the full href; to avoid closing valid connections
+      // because are not present in the pool, we check also the node url,
+      // and if is already present we update its id with the ES provided one.
+      } else if (this.connections.has(connection.url.href) === true) {
+        const oldConnection = this.connections.get(connection.url.href)
+        this.connections.delete(connection.url.href)
+        oldConnection.id = connection.id
+        this.connections.set(connection.id, oldConnection)
+        if (oldConnection.status === Connection.statuses.DEAD) {
+          this.markAlive(oldConnection)
+        }
       } else {
         this.addConnection(connection)
       }